Rounding basics

Learning Objective:

SWBAT represent a number on a number line, round to the nearest 10,

and describe the number in relation to rounding.

Demonstration of Learning:

SW represent a number on a number line, round to the nearest 10,

and describe the number in relation to rounding in at least 4

out of 5 problems.

Module2 | TopicD | Lesson13

TEKS: 3.2C represent a number on a number line as being between two consecutive multiplies of 10, 100, 1,000, or 10,000, and use
words to describe relative sized of numbers in order to round whole numbers.

Place Value and Problem Solving with Units of

Measure

Lesson Vocabulary

place value unit

rounding

vertical number line

halfway

nearest

SWBAT represent a number on a number line, round to the nearest 10, and describe the number in relation to rounding.

Halfway on the Number Line

White Board

SWBAT represent a number on a number line, round to the nearest 10, and describe the number in relation to rounding.

10

20

What number is halfway between 1 ten and 2 tens?

Halfway on the Number Line

White Board

SWBAT represent a number on a number line, round to the nearest 10, and describe the number in relation to rounding.

30

40

What number is halfway between 30 and 40?

Halfway on the Number Line

White Board

What number is halfway between 2 ten and 3 tens?

SWBAT represent a number on a number line, round to the nearest 10, and describe the number in relation to rounding.

20

30

Halfway on the Number Line

White Board

What number is halfway between 90 and 100?

SWBAT represent a number on a number line, round to the nearest 10, and describe the number in relation to rounding.

90

100

Let’s round 61 centimeters to the nearest ten. Draw number lines to model
our thinking.

Concept Development

White Board

SWBAT represent a number on a number line, round to the nearest 10, and describe the number in relation to rounding.

Concept Development

White Board

SWBAT represent a number on a number line, round to the nearest 10, and describe the number in relation to rounding.

This beaker has 73 milliliters of water in it. Show the amount on a vertical
number line.

Now, draw a vertical number line.

Let’s round 38 minutes to the nearest ten. Draw number lines to model our
thinking.

Concept Development

White Board

SWBAT represent a number on a number line, round to the nearest 10, and describe the number in relation to rounding.

Concept Development

White Board

SWBAT represent a number on a number line, round to the nearest 10, and describe the number in relation to rounding.

Let’s round 25 grams to the nearest ten. Draw number lines to model our
thinking.